Lamp bulb



March 17, 1931. MEUSH 1,796,530

LAMP BULB Filed Feb. 7, 1925 NVEIOR Patented Mar. 17, 1931 UNITED STATES PATENT OFFICE THOMAS G. MELISH, OF CINCINNATI, OHIO, ASSIGNOR TO THE CINCINNATI PATENT ENGINEERING COMPANY, OF CINCINNATI, OHIO, A CORPORATION OF OHIO LAMP BULB Application filed February directions and for purposes intended to ac-' complish highly desirable results. For example, it is frequently desirable to so reduce or change the beam of projected light so that it will not interfere with the vision of the driver of an approaching vehicle or of a pcdestrian. Also it is frequently desirable, when a vehicle is traversing a curve in a road way, to so direct the beam of light that it will be thrown substantially in the direction of the vehicle travel in traverslng the curve.

It is an object therefor to produce a lamp bulb designed, in one instrumentality, to bring about the accomplishments outlined above, through suitable circuit connections.

These and other objects are attained in the lamp bulb described in the following specification and illustrated in the accompanying drawing, in which:

Fig. 1 is a front view, such as is obtained in looking at the lamp bulb embodying my invention, when it has been installed in the usual automobile head lampl Fig. 2 is an elevational view of my improved lamp bulb.

In my invention a lamp bulb embodying four filaments is illustrated. One of these filaments, designated by filament 3, is provided for the projection of the main beam of light intended for straight ahead roadway illumination. The smaller filament 4 which is located above the large filament 3 is intended-for so called dimming purposes in order to avoid objectionable glare which would be occasioned by the filament 3. As a matter of fact the illumination of filament 4 is not intended to produce a less brilliantly illuminated roadway but merely to provide for a redirecting of the light rays so that they are given a substantial downward inclina- 7, 1925. Serial N0. 7,694.

tion, thus avoiding direct projection into the eyes of the approaching driver or pedestrian. In addition to these two filaments I have provided two other filaments 5 and 6 which are positioned to each side of the previously mentioned filaments 3 and 4. In referring to the View shown in Fig. 1, the illumination of filament 5 will bring about a projected beam of light to the right, and when filament 6 is illuminated the beam of light will be projected to the left as viewed in Fig. 1. In speaking of the direction of beam projection it must be borne in mind that the assumption is made that a reflector of proper design, as found in automobile head lamps, is located back of the bulb and at a proper distance therefrom.

Each of the filaments is supported substantially and at the proper distance with relation to the locating pin 7, on the base 8, as is usual in bulb construction, by means of suitable posts 9. These posts are connected with the base 8 and with terminals 10, 11,12 and 13 by means of leads 1-1- to 18 inclusive which are indicated somewhat diagrammatically by dotted lines. Specific description of the rela- .lion of the posts to one another is immaterial,

but itis essential that. one post serves as a common terminal for one of all the filaments, the rei'i'iaining posts having their'own location and terminal connection so that the separate filaments may be separately illuminated. A circuit to bring about the separate illumination of the several filaments, is essential, whether it be manually or automatically oper ated in some manner, but. in as much as the invention herein disclosed does not relate to such a circuit, no attempt has been made to illustrate or describe that which, in applicants opinion. lies within the province of one usually skilled in such matters.

Having thus described my invention what I claim is:

A lamp bulb including a series of filaments, and a separate circuit connection for each filament, one set of opposed filaments being located one filament on each side of the lamp bulb axis, a third filament being locatedsubstantially in the lamp bulb axis and between the first mentioned filaments, and another of said filaments being located out of axial alignment with the bulb and the first and second mentioned filaments.

In testimony whereof I have hereunto aflixed my signature.

THOMAS G. MELISH. 

